Process and apparatus for producing covered elastic thread



April 7, 1959 o. w. SCHLUMS 2,880,566

PROCESS AND APPARATUS FOR PRODUCING COVERED ELASTIC THREAD Filed March 29, 1955 7m 1: Q i 9 l I I: I Tl )h M 01 I :1 m i Q I I I "J1 I a .4

INVENTOR.

OTTO W. SCHLUMS.

ATTY

United States Patent PROCESS AND APPARATUS FOR PRODUCING COVERED ELASTIC THREAD Otto W. Schlums, Whitinsville, Mass., assignor to Whitin Machine Works, Whitinsville, Mass, a corporation of Massachusetts Application March 29, 1955, Serial No. 497,609

2 Claims. (CI. 57-12) This invention relates to an improved process of producing covered elastic thread and to apparatus for carrying out this improved process in a preferred manner.

More specifically, the invention relates to the production of covered elastic thread in which the covering material comprises a tow of synthetic fibers, which have been drafted and broken or otherwise reduced to substantially staple lengths. This tow is twisted with and about a tensioned elastic thread in my improved covering operation.

It is the general object of my invention to provide an improved process and improved apparatus by which a plurality of continuous filaments may be drafted and broken to provide a tow of staple lengths, and by which an elastic thread may receive a covering thereof as a direct continuation of the drafting and breaking operation.

Preferred apparatus by which the improved process may be conveniently carried out is shown in the drawings, in which Fig. 1 is a diagrammatic sectional elevation of drafting and covering apparatus well adapted for use in the improved process; and

Fig. 2 is a front elevation, looking in the direction of the arrow 2 in in Fig. 1.

Referring to the drawings, I have shown parts of a drafting apparatus of commercial form and comprising a back roll 10, a front roll 11, pressor rolls 12 and 13 associated with the back roll 10, and a pressor roll 14 associated with the front roll 11.

The pressor rolls 12, 13 and 14 are preferably covcred with layers 15 of resilient or cushion material. The rolls and 11 are continuously rotated at predetermined speeds but with the surface speed of the front roll 11 somewhat greater than the surface speed of the back roll 10, so that a draft between the back and front rolls is produced.

Bobbins B are mounted on rapidly rotated spindles 16, and the usual ring rail 17 supports rings 18 provided with travelers 19. Yarn guides 20 are mounted on a fixed support or rail 21 and are vertically aligned with the spindles 16. A bracket 23 is associated with each spindle 16 and these brackets are mounted on a fixed rod 22. Each bracket 23 is provided with three tensioning snubbers 25.

A fixed creel frame 26 supports rods or spindles 27 on which spools S are mounted. These spools provide a plurality of tows of continuous and untwisted filaments, and each such tow is delivered to the back roll 10 through the snubbers 25 and partially around the pressor roll 12.

Between the back roll 10 and the front roll 11, the continuous filaments in the tow 28 are drafted and broken to provide a tow 29 of substantially staple length fibers.

An elastic thread R to be covered is supplied from a storage roll 30 resting on and in contact with a driven feed roll 31. The thread R is delivered to the front roll 11 substantially at its point of contact with the pressor roll 14, and the tow of staple length fibers 29 is simultaneously delivered adacent the same point.

The feed roll 31 has a relatively slower surface or peripheral speed than the front roll 11, so that the elastic thread R is stretched and is under tension at its point of delivery to the front roll 11. The thread R may have a certain amount of initial twist, as indicated by the shading on the drawing.

As the tensioned elastic thread R and the drafted tow 29 of staple length fibers leave the front roll 11 and the pressor roll 14, these combined products are twisted by the rapid rotation of the spindle 16, and a suitably covered thread will thus be rapidly produced.

The initial twist in the thread R, if any, may be additional to the twist imparted by the spindle 16, or it may be deducted therefrom, depending on the hand of the initial twist in the thread R.

By the use of this improved continuous process, a substantial reduction in the amount of associated apparatus is made possible.

Having thus described my invention and the advantages thereof, I do not Wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. In an apparatus for covering elastic thread, a front drafting roll and a back drafting roll, means to rotate said rolls and to give the front roll a greater peripheral speed, front and back pressor rolls coacting with said front and back drafting rolls, means to supply a tow comprising a plurality of continuous synthetic filaments to said back rolls, which filaments are drafted and broken to staple length fibers between said back rolls and said front rolls by the differential peripheral speeds thereof, means to supply an elastic thread, means to give a predetermined stretch and tension to tension said thread, said tensioned elastic thread being presented to said front rolls adjacent the point at which the tow of staple length fibers are nipped by said front rolls, and directly-adjacent means to twist said tensioned elastic thread and said tow of untwisted staple length fibers to form a fiberenclosed elastic thread.

2. The improved process of producing a covered elastic thread which comprises providing a tow of untwisted continuous synthetic filaments, drafting and breaking said continuous filaments to staple length fibers, supplying a rubber thread, giving said rubber thread a predetermined and substantial stretch, immediately and continuously presenting the untwisted tow of staple length fibers to the tensioned and stretched rubber thread, and directly twisting the tensioned rubber thread and the untwisted tow of staple length fibers together to form a fiber-enclosed rubber thread.

References Cited in the file of this patent UNITED STATES PATENTS 2,024,156 Foster Dec. 17, 1935 2,132,524 Booth Oct. 11, 1938 2,300,241 Van Voorhis Oct. 27, 1942 2,523,854 Woods Sept. 26, 1950 2,526,523 Weiss Oct. 17, 1950 2,588,361 Cooper Mar. 11, 1952 

